Customer Discovery for Deep Tech: Stop Pitching, Start Learning (Pt1)
In this edition of Meet The Experts, we’re speaking with Felix Günther, a customer discovery expert with a background in economics, entrepreneurship, and venture building.
In our conversation, we explored a wide range of topics, including:
accepting that you do not know
understanding the customer before pitching
choosing and testing a market
personal outreach and founder-led discovery
How do you find a market when you are still figuring out who actually needs your technology?
For customer discovery expert Felix Günther, the answer starts with something deceptively simple: accepting that you do not know.
Felix first stumbled into customer discovery while building his own company and found himself drawn to talking to customers and understanding why they were, or were not, interested.
“It was almost like playing Sherlock Holmes,” he remembers: understanding people’s lives, situations, goals and what holds them back. Only later did someone tell him that what he was doing had a name: Customer Discovery.
He then learned the craft systematically in corporate venture building. A corporate client would bring him a concept or technology, and his job was to find out whether anyone out there would potentially pay for it, why, and how to find more of those people. For deep tech founders, that is a familiar situation: you start with what you can build, and you still have to find the people who need it.
Curiosity Before Expertise
For Felix, good customer discovery doesn’t start with a framework but with a mindset.
“It’s a lot about intrinsic motivation to understand the other side, to accept that you don’t know, and to have a wish to change that. If you combine this with learning to listen more than you pitch, you have everything you need.”
That matters especially when you have spent years becoming an expert.
A founder might look at an existing process and immediately think: this takes them two hours, with our technology it would take 20 minutes, so obviously they should use it. Felix argues that this starts in the wrong place.
Instead, ask why the process exists. What comes before and after it? What alternatives have people tried? Why have they stayed with the current solution? People usually have a reason for how they ended up where they are, and reasons for not changing.
Or as he puts it, “Before you throw your stuff at them, understand their world.”
The payoff comes later. Felix contrasts two ways of pitching. In the first, you list 17 features and hope one of them lands. In the second, you ask what matters first and then show the one feature you are fairly sure is relevant. In other words, understanding someone's world first doesn't delay the pitch, it actually makes the pitch work.
You Probably Don’t Need the Website Yet
Early-stage founders often feel pressure to look like a finished company before they fully understand what company they are building.
Felix thinks much of this can wait. “At this stage, I don’t need a landing page. I don’t need a company name. I don’t need anything like that,” he says. “All I want is to invite you for a coffee, or have a 20-minute Zoom call.”
His reasoning is practical. Nobody will find your landing page, because nobody knows you exist. And because the outreach is personal rather than a company pitch, people have no reason to check whether your company looks legitimate. The conversation is between two people, not between a startup and a prospect.
In that call, Felix asks about the other person's goals, how they pursue them, and where their current options fall short. Most of the time, it becomes clear there is no fit, and the conversation ends politely. Only when there appears to be a genuine match does he change gears: he mirrors back what he has heard and asks whether the person would like to see a different approach.
“Everything up to here was me trying to understand you, which is the discovery,” he says. Once the person confirms that the situation is relevant and wants to hear more, “it becomes a sales call.”
Those conversations are also where the website copy comes from. Once Felix has found five, ten or fifteen people who have confirmed they want to hear about the technology, "I build a vocabulary. I build an understanding about what matters to them. And then I have the foundation from which I'm going to build my landing page."
This isn't an argument against websites. Later, once a team knows who buys what and why, and people other than the founders start selling, a proper company presence becomes necessary. The point is that the sequence matters: focus on the customer's vocabulary first, the website second.
Pick a Market, Even If It Is the Wrong One
Deep tech technologies often have many possible applications. That optionality can feel like an advantage, but Felix repeatedly sees it turn into paralysis.
Early-stage founders don't want to say no to anything, which is understandable when you depend on every opportunity. But the result is that they "spread the butter really thin." When they write one message meant to fit every possible segment, it "ends up being relevant for none."
The most extreme case Felix remembers was a B2B software team that had raised around €800K, had about six people working on the company for more than a year, and was pursuing 12 industry use cases… but they had no customers. The team was chasing every lead for a follow-up meeting, while no one was asking them for one. Once they narrowed their focus to two use cases, the company landed its first clients within about three weeks.
The solution is not to identify the perfect market upfront. It is to choose somewhere to start: “Into what direction do we want to go first, knowing that the probability that this won’t be our perfect market is rather likely?”
Next, Felix asks teams to write down their assumptions: What does this target group want to achieve? Why? What options do they have? Why are those options unsatisfying? It's a short exercise, but a powerful one, especially for founding teams that haven't compared notes in a while.
Then comes focus. A team might spend six weeks going all in on automotive, pausing everything else: no outreach to other industries, no conferences outside that field. Teams with enough capacity can run two markets in parallel, for example with two founders each spending around 30 hours a week on it, but Felix tries not to go beyond two. Every other week, the team compares what they believed with what they have learned and decides whether to continue, adjust or move on.
"We have our clear focus and we go all in for this one," he says. "We can stop this direction at any point. But then we properly stop it and go to the next one."
Outreach Is Human-to-Human
After years of becoming highly competent in one domain, entrepreneurship suddenly asks founders to enter unfamiliar industries, approach strangers and deal with rejection. This can be quite uncomfortable for researcher-turned-founders.
"My theory, and this might be wrong, is that researchers feel very comfortable in the lab," Felix says. After a decade or more of building expertise, a non-response from a stranger stings differently; it feels more personal than an experiment going badly. "So there is this tendency to shy away from that."
His answer is to make outreach more human, not more sales-like. “Your task is not to sell them something they don’t need. Your task is to understand their world.”
That also means resisting automation too early. Sending hundreds of people the same value proposition assumes you already know who matters and what they care about. Instead, Felix recommends short, personal messages: explain why you want to speak to that person, give enough background, and make a concrete request to meet: “Keep it short, keep it personal. Explain why you want to speak with them.”
And expect to do a lot of it. Getting to ten customers can mean talking to well over 100 people. For pre-seed and seed-stage teams, Felix suggests a simple benchmark: five customer calls a week. Ten is even better.
"It's a numbers game. Input equals output, and you become better over time," he says. "Five more. Little steps. Be persistent and open-minded, and then you're either going to find your niche or figure out that you should change the path."
The Bottom Line
Customer discovery is not about proving that your original idea was right, it is about becoming systematically less wrong.
Felix sees two recurring problems. "Founders just don't put enough effort into outreach. They underestimate it completely," he says. And when founders do get a discovery call, "They pitch their product instead of asking questions."
The better starting point is the opposite: choose a direction, write down your assumptions, go out and test them, and listen long enough to understand somebody else's world.
But listening is only half the job. Felix recommends The Mom Test: How to talk to customers & learn if your business is a good idea when everyone is lying to you by Rob Fitzpatrick as a good introduction to asking better questions, but he thinks it can leave founders "in a very comfortable place," with plenty of pleasant conversations and no real evidence. Eventually, you have to ask for commitment and see how people react. That's what Part 2 is about.
In Part 2, we look at how Felix distinguishes polite interest from genuine customer pull, why an early pilot is still part of discovery, and how success stories can turn a highly personal founder-led process into repeatable sales.